Based on some great info that I got from these threads, I did something very different than the regular Disney autograph books. I went to Michaels Arts & Crafts store and bought 2 hard cover, 3 ring binders on clearance. It measured about 8 x 9. Then I bought a package of 8 1/2 x 11 card stock paper and cut that in half. I punched holes on each page and put on those little round hole re-inforcers. My kids decorated each page with stickers and designs that they colored. They even made pages especially for their favorite characters to sign. When the characters saw they had a special page, they made a big deal out of it. My daughter was thrilled. When we came home, I added some photo pages that you can buy as fillers and the kids placed their pictures, as well as park guides, resort map, room key and any other souvenier that they thought "special". It's nice having it all in one place and cute to look back through what was special to them at that time.
The books were big enough to be easily found in a backpack and we tied the fat pen right onto one of the rings so we never had to search for them when we saw a character.